: A Convenient System for Synthesis of Oximes from the Corresponding of Organic Carbonyl Compounds

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1 ORIENTAL JOURNAL OF CHEMISTRY An International Open Free Access, Peer Reviewed Research Journal ISSN: X CODEN: OJCHEG 206, Vol. 32, No. (3): Pg OH.HCl/ : A Convenient System for Synthesis of Oximes from the Corresponding of Organic Carbonyl Compounds Farhad Talaei and Davood Setamdideh* Department of Chemistry, Mahabad Branch, Islamic Azad University, Mahabad, Iran. *Corresponding author davood.setamdideh@gmail.com (Received: October 08, 205; Accepted: November 7, 205) Abstract A variety of aldehydes and ketones were converted to their corresponding oximes OH HCl/ system in reflux conditions. Keywords: Oximes, aldoximes, acetophenone oximes, H 2 NOH.HCl,. Introduction Oximes have many applications in organic synthesis. These compounds have antimicrobial, antioxidant, antitumor, anti-depressive, antiviral agents, and anticonvulsant properties 2-7. Some oximation methods have been reported 8. However our ongoing attentions to the development of new modified methods in organic synthesis 8-5, we have investigated the oximation of a variety of carbonyl compounds with OH HCl in the presence of. Results and Discussions For finding optimization reaction conditions bezaldehyde and acetophenone have been used as model compounds. Experiments showed that using OH.HCl (.2 mmol) and ( mmol) in C 2 H 5 OH (3 ml) was the best conditions for the oximation of benzaldehyde. The reaction was completed within 30 minutes in reflux conditions with the excellent yield (95%) of the product as shown in scheme. H O OH.HCl (.2 mmol), ( mmol) C 2 H 5 OH (3 ml), reflux, 30 min, Conversion 00% H NHOH Scheme :

2 Talaei & Setamdideh, Orient. J. Chem., Vol. 32(3), (206) 584 Table : Oximation of Aldehydes ( mmol) by OH.HCl (.2 mmol)/ ( mmol) Under Reflux Conditions in Ethanol (3 ml) Entry Substrate Product H chemical Time(min) HNMR(δ ppm), IR (cm - ) and m.p. ( C) 7 shift of C(H) Yield(%) a =N(δ ppm) benzaldehyde (Z)-benzaldehyde , 95 HNMR (CDCl3 ) (m, 5H, Ar), 8.0 (bs, H, OH), oxime 8.8 (s, H, CH). IR (liquid film) 3308 (NOH), 694, 497, 450, 294, 073, 958, 756, 69. m.p (Z)-4- benzaldehyde , 95 HNMR (CDCl3 ) 5.2 (bs, H, OH), (m, 4H, Ar), bromobenzaldehyde oxime 8.0 (H, CH). IR (KBr) 3367 (NOH), 70, 589, 489, 365, 067, 968, 703. m.p b N,N- (Z)- N, , 96 HNMR (CDCl3 ) 3.0 (s, 6H, CH 3 ), 5.3 (s, H, OH), 6.69 dimethylbenzaldehyde N-dimethyl (d, 2H, Ar), 7.46 (d, 2H, Ar), 8.07 (s, H, CH). benzaldehyde IR (KBr) 3237 (NOH), 6, 447, 00, 8, 736. oxime m.p b 4-methylbenzaldehyde (Z)-4-methyl , 93 HNMR (CDCl3 ) 2.38 (s, 3H,CH 3 ), 7.2 (d + bs, 3H, Ar + benzaldehyde OH), 7.49 (d, 2H, Ar), 8.5 (s, H, CH). oxime IR (KBr) 3400 (NOH), 635, 409, 265, 040, 896, 740. m.p b 3- (Z)-3-methyl , 92 HNMR (CDCl3 ) 2.38 (s, 3H,CH3), (m, 4H, Ar), methylbenzaldehyde benzaldehyde 7.82 (bs, H, OH), 8.5 (s, H, CH). oxime IR (liquid film) 334 (NOH), 632, 584, 489, 40, 309, 266, 954, m.p nitrobenzaldehyde (Z) , 93 HNMR (CDCl3 ) 7.76(d, 2H, Ar), 8.23 (d + bs, 3H, Ar + OH), nitrobenzaldehyde 8.27 (s, H, CH). oxime IR (KBr) 3077 (NOH), 603, 535, 348, 08, 970, 847, 748, 686.

3 Talaei & Setamdideh, Orient. J. Chem., Vol. 32(3), (206) 585 m.p b 2- (Z)-2-methoxy , 97 HNMR (CDCl3 ) 3.89 (s, 3H,OCH 3 ), 5.97, (bs, H, OH), 6.97 methoxylbenzaldehyde benzaldehyde (q, 2H, Ar), 7.38 (t, H, Ar), 7.68 (d, H, Ar), oxime 8.49 (s, H, CH). IR (KBr) 3304 (NOH), 632, 497, 449, 299, 2, 957, 870, 756, 692. m.p b 4-methoxybenzaldehyde (Z) , 98 HNMR (CDCl3 ) 3.84 (s, 3H,OCH 3 ), 6.92 (d, 2H, Ar), 7.53 methoxy (d + bs, 3H, Ar + OH), 8. (s, H, CH). benzaldehyde IR (KBr) 332 (NOH), 606, 54, 254, 75, oxime 956,832, 835. m.p a Yields refer to isolated pure products (±2%). A variety of aldehydes were ground with system under optimized reaction conditions. In this approach, the corresponding Z-aldoximes were obtained in quantitative yield (93-98%). The results have been reported in table. Then, the oximation of ketones was also performed well by system. Experiments showed the oximation of ketones requires higher molar amounts of NH2OH HCl (.5 mmol) and ( mmol) vs. mmol of the substrates. The reaction of acetophenone was completed in 65 minutes with the excellent yield (93%) as shown in scheme 2. A variety of acetophenones were ground with system under optimized reaction conditions. In this approach, the corresponding E-acetophenonoximes were obtained in quantitative yield (87-95%). The results have been reported in table 2. All substrates and reagents were purchased from commercially sources with the best quality. IR and H NMR spectra were recorded on PerkinElmer FT-IR RXI and 300 MHz Bruker spectrometers, respectively. The products were characterized by their H NMR or IR spectra and comparison with authentic samples (melting points). All yields referred to isolated pure products. The purity of products was determined by TLC and H NMR. Also, reactions were monitored by TLCs utilizing plates cut from silica gel 60 F 254 aluminum sheets. A typical procedure for the oximation with system In a round-bottomed flask (0 ml) equipped with a condenser, a mixture of benzaldehyde (0.06 g, mmol), OH HCl (0.084 g,.2 mmol) and (0.2 g, mmol) in ethanol (3 ml) was prepared. The mixture was stirred under reflux conditions for 30 min. The progress of the reaction was monitored by TLC. After completion of the reaction, H 2 O (0 ml) was added and the reaction mixture was continued to stirring for 5 min. The product has been extracted with CH 2 Cl 2 (3õ5 ml).the mixture was dried over anhydrous Na 2 SO 4. Evaporation of the solvent and a short column chromatography of the resulting crude material over silica gel (eluent; CCl 4 /Et 2 O: 5/2) afforded the pure benzaldoxime (0.5 g, 95 % yield, table, entry ).

4 586 Talaei & Setamdideh, Orient. J. Chem., Vol. 32(3), (206) Table 2: Oximation of Ketones ( mmol) by OH.HCl (.5 mmol)/ ( mmol) Under Reflux Conditions in Ethanol (3 ml) Entry Substrate Product H chemical Time(Sec) HNMR (δ ppm), IR (cm - ) and m.p.( C) 7 shift of CH 3 Yield (%) a (δ ppm) acetophenone (E) , 93 HNMR (CDCl3 ) 2.34 (s, 3H, CH 3 ), (m, 5H, Ar), acetophenone 8.0 (s, H, OH). oxime IR (KBr) 3305 (NOH), 630, 602,498, 446, 26, 096, 925, 757, 695. m.p (E) , 87 HNMR (CDCl3 ) 2.3 (s, 3H, CH 3 ), 2.38 (s, 3H, CH 3 ), 6.35 methylacetophenone methylacetophenone (s, H, OH), 7.2 (d, 2H, Ar), 7.54 (d, 2H, Ar). IR (KBr) 3397 (NH), 636, 420, 265, 095, 87, 739. oxime m.p (E) , 90 HNMR (CDCl3 ) 2.3 (s, 3H, CH 3 ), 3.83 (s, 3H, OCH 3 ), 6.9 methoxyacetophenone ethoxyacetophenone (d + bs, 3H, Ar + OH), 7.58 (d, 2H, Ar). oxime IR (KBr) 3305 (NOH), 602, 446, 26, 096, 925, 757. m.p benzalacetone (E) , 95 HNMR (CDCl3 ) 7.28(Ar, 2H), 6.87(Ar, 2H), 4.8 (CH, H), benzalacetone 3.78(OCH 3, 3H), 2.53 (OH, H),.45 (CH 3, 3H). oxime IR (KBr) 327 (NOH), 633, 448, 260, 029, 964, 802, 034, 749, 69. m.p. -3 a Yields refer to isolated pure products (±2%).

5 Talaei & Setamdideh, Orient. J. Chem., Vol. 32(3), (206) 587 H 3 C O OH.HCl (.5 mmol), ( mmol) C 2 H 5 OH (3 ml), reflux, 65 min, Conversion 00% H 3 C NHOH Scheme 2: Conclusion The oximation of a variety of aldehydes and ketones was carried out efficiently with OH HCl/ system. The reactions were performed in ethanol under reflux conditions. Excellent yields (93-98%) of products in appropriate times (30-00 min) have been achievement. Acknowledgements The authors gratefully appreciated the financial support of this work by Islamic Azad University branch of Mahabad. References. Xia, J. J.; Wang, G. W. Molecules 2007, 2, Li, H. Q.; Xiao, Z. P.; Yin, L.; Yan, T.; Lv, P.C.; Zhu, H. L.. Eur. J. Med. Chem. 2009, 44, Karakurt, A.; Sevim, D.; Özalp, M.; Özbey, S.; Kendi, E.; Stables, J. P. Eur. J. Med. Chem. 200, 36, Puntel, G. O.; de Carvalho, N. R.; Gubert, P.; Palma, A. S.; Corte, C. L. D.; Ávila, D. S.; Pereira, M. E.; Carratu, V. S.; Bresolin, L.; J. Da Rocha, B. T.; Soares, F. A. A. Chem. Biol. Interact. 2009, 77, Wang, T. C.; Chen, I. L.; Lu, C. M.; Kuo, D. H.; Liao, C. H Chem. Biodivers. 2005, 2, De Sousa, D. P.; Schefer, R. R.; Brocksom U.; Brocksom, T. J. Molecules 2006,, Ouyang, G.; Chen, Z.; Cai, X. J.; Song, B. A.; Bhadury, P. S.; Yang, S.; Jin, L. H.; Xue, W.; Hu, D.Y.; Zeng, S. Bioorg. Med. Chem. 2008, 6, Setamdideh, D.; Khezri, B.; Esmaeilzadeh, S. J. Chin. Chem. Soc. 202, 59, Setamdideh, D.; Khezri, B.; Alipouramjad, A. J. Chin. Chem. Soc. 203, 60, Sofighaderi, S.; Setamdideh, D. Orient. J. Chem. 203, 29, Setamdideh, D.; Sepehraddin, F. J. Mex. Chem. Soc. 204, 58, Azizi Asl, P.; Setamdideh, D. J. Chin. Chem. Soc. 204, 59, f) Setamdideh, D. J. Mex. Chem. Soc. 204, 58, Azimzadeh, M.; Setamdideh, D. Orient. J. Chem., 205, 3, Rezaeekhoredehforosh, R.; Khezri, B.; Setamdideh, D. Orient. J. Chem., 205, 3, Mahmoudi, M.; Setamdideh, D. Orient. J. Chem., 205, 3,